Abstract: The present invention is designed to provide a radio base station apparatus, a mobile terminal apparatus, a radio communication system and a radio communication method which can cope with an increased number of users. A radio base station apparatus is provided with: a signal generating section that generates a first downlink control signal and a second downlink control signal for a mobile terminal apparatus; a first multiplexing section that multiplexes the first downlink control signal on a control region up to a predetermined number of symbols from the top of a subframe; a second multiplexing section that frequency-division-multiplexes the second downlink control signal on radio resources from the next symbol in the control region to the last symbol of the subframe; and a transmission section that transmits the first downlink control signal multiplexed on the control region and the second downlink control signal multiplexed on the radio resources.

Abstract: A radio base station communicates with mobile terminals and is configured to be able to execute radio transmission to the mobile terminals using resources that are the same as resources used by a second radio base station forming a second cell having a smaller area within a first cell formed by the radio base station itself and is configured to collaborate with the second radio base station for inter-cell interference control. The radio base station sets a modulation system having a modulation level that is less than that of the modulation system provisionally determined as the modulation system for mobile terminals to which a resource group having a low transmission power is assigned and adjusts transmission parameters in a case in which the modulation system provisionally determined for the mobile terminals to which the resource group having the low transmission power is assigned, is inappropriate for the low transmission power.

Abstract: A transmission apparatus is provided with radio resource assignment means that assigns radio resources to each physical channel according to a type of the physical channel; and transmission means that transmits information to be transmitted by each physical channel using the assigned radio resources.

Abstract: It is an object of the present invention to provide a reference signal transmitting method, a mobile terminal apparatus and a base station apparatus capable of reducing influences on a PDCCH even when performing transmission control over an aperiodic reference signal for measuring channel quality.

Abstract: A communication terminal in a multi-carrier system using a frequency bandwidth including a plurality of resource blocks, each of the resource blocks including one or more sub-carriers. The communication terminal includes a receiving unit configured to receive a signal in which a control channel is multiplexed into a single radio frame based on a number of control channels allocated into the single radio frame to use a lower coding rate by repeating transmitting without changing encoding method in which a channel other than the control channel is multiplexed in accordance with scheduling information for allocating one or more of the plurality of resource blocks to the communication terminal and a processing unit configured to perform a process on the signal received by the receiving unit.

Abstract: To signal CSI-RS location indexes indicative of CSI-RS location positions in a resource block with high efficiency, a signaling method of CSI-RS is characterized by having the steps of locating a CSI-RS that is a reference signal for downlink channel estimation in resources for CSI-RS reserved to transmit the CSI-RS, generating a CSI-RS location index indicative of a location position of the CSI-RS located in the resources for CSI-RS, in the CSI-RS location index an index pattern varies corresponding to the number of CSI-RS ports so that an index pattern of the relatively low number of CSI-RS ports is a subset of an index pattern of the relatively high number of CSI-RS ports, and transmitting the generated CSI-RS location index to a mobile terminal apparatus.

Abstract: A radio communication system includes multiple radio base stations and multiple mobile communication terminals. Each mobile communication terminal measures a reception quality of radio waves from each radio base station. A first mobile communication terminal that can execute interference rejection combining offsets the reception quality value of radio waves from a second radio base station by using a first bias value. A second mobile communication terminal that cannot execute interference rejection combining offsets the reception quality value of radio waves from the second radio base station by using a second bias value that is lower than the first bias value. The first radio base station selects, as the radio access point for the mobile communication terminal, a radio base station corresponding to a reception quality value indicating a best reception quality among the first reception power value and the offset second reception power value.

Abstract: To effectively improve the reception quality in a pico-base station, while preventing throughput of a macro-base station from significantly deteriorating, a macro-base station (M-BS) is provided with a beam generating section (35) that generates a directional beam to a macro-UE using antenna weights based on a beampattern assigned to the macro-UE existing in a macro-cell having a first coverage area, and a coordination section (36) that determines a beam pattern so that a beam pattern to the macro-UE existing in the macro-cell is a beam pattern that suppresses interference power to a pico-UE existing in a pico-cell, in assigning the beam pattern to the macro-UE existing in the macro-cell during a transmission period assigned to a pico-base station (P-BS) locally forming the pico-cell in the macro-cell.

Abstract: A radio communication system includes multiple base stations including a first base station and a second base station, and a mobile station. A candidate base station selector selects multiple candidate base stations that are candidates for a radio access point for the mobile station on the basis of the reception powers reported by the mobile station. When the mobile station actually executes wireless communication with the base station, an access-point base station determiner determines, as an access-point base station that is the actual radio access point for the mobile station, a base station corresponding to a best reception quality among reception qualities measured in the protected resource and reception quality measured in the non-protected resource.

Abstract: To provide a base station apparatus, mobile terminal apparatus and communication control method for enabling control adapted to interference inside a Heterogeneous network to be performed to support the next-generation mobile communication system, a base station apparatus (20) shares at least a part of the frequency band with another base station apparatus (40) that covers a macro-cell, covers a pico-cell (C1), is capable of transmitting a downlink transmission frame at transmission timing different from the another base station apparatus (40), and is configured to set resources, in which the downlink transmission frame undergoes interference from another downlink transmission frame including a blank period transmitted from the another base station apparatus (40), as blank resources, and assign user data to the downlink transmission frame while avoiding the blank resources.

Abstract: A mobile station is classified into one of plural classes based on the reception quality from a base station. The allocations of resource blocks are executed at the base station so that a resource block used for the transmission of a data signal component for a mobile station in a class is not commonly used as a resource block for the transmission of a data signal component for another mobile station belonging to the same class but is commonly used as a resource block used for the transmission of a data signal component for a mobile station belonging to another class. A mobile station, based on the allocation of resource blocks, demodulates a data signal component corresponding to the mobile station after cancelling a data signal component corresponding to a low-quality mobile station.

Abstract: In order to report aperiodic channel state information (A-CSI) flexibly even when a user terminal performs radio communication using a plurality of component carriers (CCs) in an HetNet environment, the present invention provides an aperiodic channel sate information reporting method comprising: a step of transmitting in advance, from a pico base station (PeNB) to pico UE, channel state measurement target information having information about presence or absence of reporting of channel state information and a subframe as a measurement target associated with trigger bit information indicating information about presence or absence of reporting of channel state information and a component carrier as a measurement target (step ST401); and a step of reporting channel state information of the subframe and the component carrier designated by the trigger bit information transmitted on a PDCCH, to the pico base station (PeNB) on a PUSCH (step ST406).

Abstract: A user apparatus transmits an uplink control signal to a base station apparatus using a single carrier scheme. The user apparatus includes: a unit configured to prepare acknowledgement information indicating positive acknowledgement or negative acknowledgement for a downlink data signal based on a result of demodulation of the downlink data signal; a unit configured to prepare channel state information indicating reception quality of a downlink reference signal; a unit configured to channel-code multiplexed control information in which the acknowledgement information and the channel state information are multiplexed to prepare the uplink control signal; and a unit configured to transmit the uplink control signal using dedicated resources different from resources for an uplink data signal.

Abstract: A user apparatus transmits an uplink control signal to a base station apparatus using a single carrier scheme. The user apparatus includes: a unit configured to prepare acknowledgement information indicating positive acknowledgement or negative acknowledgement for a downlink data signal based on a result of demodulation of the downlink data signal; a unit configured to prepare channel state information indicating reception quality of a downlink reference signal; a unit configured to channel-code multiplexed control information in which the acknowledgement information and the channel state information are multiplexed to prepare the uplink control signal; and a unit configured to transmit the uplink control signal using dedicated resources different from resources for an uplink data signal.

Abstract: In order to implement optimal CFI control under a cross-carrier scheduling environment and improve PDSCH transmission efficiency, for the MACRO_UE2 where the cross-carrier scheduling is employed, the PDSCH initiation position of CC1 that is used to transmit PDCCH is dynamically controlled, and the PDSCH initiation position of CC2 that is not used to transmit PDCCH is quasi-statically controlled. For the PICO_UE2 where the cross-carrier scheduling is employed, the PDSCH initiation position of CC2 that is used to transmit PDCCH is dynamically controlled, and the PDSCH initiation position of CC1 that is not used to transmit PDCCH is dynamically controlled.

Abstract: A high-power radio base station includes a resource setter configured to determine a ratio of the number of second resources at which the radio communicator should stop radio transmission to the sum of the number of the second resources and the number of first resources at which the radio communicator should execute radio transmission. The resource setter determines the ratio on the basis of a first number and a second number, the first number being the number of mobile terminals that are assumed to be connected with the radio base station, rather than the low-power radio base station, when cell range expansion (CRE) is not applied, but are connected with the low-power radio base station by virtue of application of cell range expansion, the second number being the number of mobile terminals connected with the radio base station when cell range expansion is applied.

Abstract: The present invention is directed to preventing the load to be required for blind detection in a mobile station apparatus (UE) from increasing and switching between SU-MIMO and MU-MIMO dynamically, even in the event the system bandwidth is expanded. The present invention has a DCI format selection section (209) that selects identification information which identifies between a DCI format for SU-MIMO and a DCI format for MU-MIMO, a control signal generation section (210) that generates control signals including the identification information and including the DCI format for SU-MIMO or MU-MIMO, having the same number of bits, and a transmission section that transmits the control signals to a mobile station apparatus.

Abstract: The present invention is designed such that, when a user terminal performs radio communication using a plurality of serving cells of different component carriers, it is possible to flexibly report aperiodic channel state information of a serving cell required on the network side among the plurality of serving cells. A radio base station apparatus transmits an uplink scheduling grant, which includes an identification field that identifies an uplink serving cell where an uplink shared channel is allocated among a plurality of uplink serving cells and a request field that requests reporting of aperiodic channel state information from a user terminal, to the user terminal, via a downlink control channel, and the user terminal reports aperiodic channel state information of a downlink serving cell that is designated by a combination of the identification field and the request field, to the radio base station apparatus, via the uplink shared channel.

Abstract: To provide a base station apparatus, mobile terminal apparatus and communication control method for enabling control adapted to interference inside a Heterogeneous network to be performed to support the next-generation mobile communication system, a base station apparatus (20) shares at least a part of the frequency band with another base station apparatus (40) that covers a macro-cell, covers a pico-cell (C1), is capable of transmitting a downlink transmission frame at transmission timing different from the another base station apparatus (40), and is configured to set resources, in which the downlink transmission frame undergoes interference from another downlink transmission frame including a blank period transmitted from the another base station apparatus (40), as blank resources, and assign user data to the downlink transmission frame while avoiding the blank resources.

Abstract: The present invention provides a mobile terminal apparatus, a base station apparatus, and a communication control method, which allow control suitable for interference reduction in a layered network such as HetNet, and which support a next-generation mobile communication system. A mobile terminal apparatus has a receiving section (103) that receives radio frames of a pico cell, in which a protected subframe, the transmission of which by a macro cell is suppressed, and a non-protected subframe, the transmission of which by the macro cell is not suppressed, coexist, a measurement section (112) that measures reception quality from the reference signals multiplexed individually on the protected subframe and the non-protected subframe, and a transmission section (103) that notifies two types of reception quality information of the protected subframe and the non-protected subframe, measured in the measurement section (112), to a base station apparatus (20B).